The present invention relates to the use of certain thiadiazolidines as herbicides, especially as pre-emergent herbicides and to herbicidal compositions containing certain thiadiazolidines. The invention also relates to a process for preparing the thiadiazolidines.
Prior art references concerning herbicidal compositions are numerous. For example, U.S. Pat. Nos.: 3,766,202; 3,796,561; 3,822,282; 3,854,925; and 3,925,553 relate to the use of herbicides containing various substituted amino-imidazolidinediones. Prior art relevant to the structure of the compounds contained in the herbicidal composition of the present invention and used in the process of the present invention includes Angew. Chem. International Edition, 1976, "Novel 1,2,4-Thiadiazolidine 1-Oxides and 1,1-Dioxides from 2-Imino-1,3-thiazetidines," by Walter Ried et al, pages 103-104. This latter reference discloses a compound having the same general formula as the compounds used in the present invention and wherein R.sup.1 is methyl and R.sup.2 is phenyl which is, thus, identical to one of the preferred compounds contained in the herbicidal composition of the present invention.